Lrl from Italy

[pigeon]

Originally Posted by taxma1981

Hi again and sorry for my englisch,
the additional circuit is not for the circuit of Frank..it is for the circuit battlfield lazer detector...this circuit with a crystal oscillator and a LC circuit working well.....

hi taxma


you can forget your pcb.

thank you

[taxma1981]

today i throw away and the two receivers, it is not possible to work one day and then not do anything ...

[pigeon]

Originally Posted by taxma1981

today i throw away and the two receivers, it is not possible to work one day and then not do anything ...

[darkman]

hi franco , and all
i removed the quartz and changed c13+c14= 7.4nf, until i got 0.04v DC on output . then i get back the quartz to the Bord and replace c2,c3,c4 with 6.6pf , i got 4.7 volts on output .
when i move my hand near the Bord the output volt drop up to 6 vdc .
in stand by mood :
tr2 collector = 4.7 vdc .
tr3 collector = 4.9 vdc .
tr4 collector = 5.3 vdc .
tr5 Emitter = 4.7 vdc .
L1 is 3 terns 1cm diagram with 22pf on c10 , i used 25cm to 1m of stylus antenna .
note: when i Touch the antenna the output volt jump from 4.7 vdc To 5.6 vdc . (but in test field the first led is off ).
* 2 days ago i went to test field , i got 400 grams of Yellow and red copper buried for 3 month's , 30cm depth , but without any Result , the lrl are not Responds >>
what did u think franco , where is the problem ?

[FrancoItaly]

Hi darkman,

The values seem correct, the correct value of sensitivity is a bit less than the beginning of the compass effect. Have you tried this test? If you are unable to have this effect means that there is not enough amplification. This is confirmed by the fact that you are using 6.6pF for C2, C3 and C4, typically this value is about 1pF. Also for the gain of the stage it is the rule that maximum gain is before the stage starts to self oscillate. Controls the gain of TR2, TR3 and Tr4, beta must be 500 or higher, try to lower the value of R10-R12 from 1K to 560 ohms or less. Of course there is also the possibility that the buried metal not issue the "phenomenon."

Best regards

[afshin]

Hi Taxma
Your project is very good,I have a question Mr Taxma:
What is the number of ferrite beads used in this circuit?
(Number or mark)
Thanks

[taxma1981]

I dont know my friend,not something writes,a friend gave me this ferrite,this man make radio

[afshin]

Thanks Taxma

[darkman]

Originally Posted by FrancoItaly

Hi darkman,

The values seem correct, the correct value of sensitivity is a bit less than the beginning of the compass effect. Have you tried this test? If you are unable to have this effect means that there is not enough amplification. This is confirmed by the fact that you are using 6.6pF for C2, C3 and C4, typically this value is about 1pF. Also for the gain of the stage it is the rule that maximum gain is before the stage starts to self oscillate. Controls the gain of TR2, TR3 and Tr4, beta must be 500 or higher, try to lower the value of R10-R12 from 1K to 560 ohms or less. Of course there is also the possibility that the buried metal not issue the "phenomenon."

Best regards

Thx mr franco ..
I mean that I removed c2, c3, c4 then I put 1capester 6.6pf .. sorry for my English
Thx

[darkman]

Originally Posted by darkman

Thx mr franco ..
I mean that I removed c2, c3, c4 then I put 1capester 6.6pf .. sorry for my English
Thx

sorry i was Wrong , (2 of 1pf capacitor in parallel +1pf in series) total capacity of c2,c3,c4 is 1.5pf ..

regards

[eroll]

Hello

I want to add sprint lay file of abdou2014 picture of 8mhz version

I added 470 k pot I hope İt is correct place

[Nicolas]

Originally Posted by eroll

Hello

I want to add sprint lay file of abdou2014 picture of 8mhz version

I added 470 k pot I hope İt is correct place

Hi Erol.

Thank you welcome at our forum

best regards
Nicolas

[eroll]

Hello All

Abdou2014 sprint lay6 file at link 8mhz Franko İtaly Lrl

https://yadi.sk/d/MyhXySWExGNC2

Abdou are you success to built this version?

any hint ?

[abdou2014]

Other version with varicap diode

[GOLDEN LILLY]

Here is my LRL based on franco's design.

[GOLDEN LILLY]

Why is it my attachment cannot be viewed? I followed instructions to post image here in manage attachment but still it cannot be viewed.

[pigeon]

Originally Posted by aulook

Why is it my attachment cannot be viewed? I followed instructions to post image here in manage attachment but still it cannot be viewed.

[GOLDEN LILLY]

My Franco lrl... Very sensitive. I have not yet tested on the field. But initial test is promising..

Regards...

[FrancoItaly]

well done, I see you've also put a compass, it is almost essential because the response is very dependent on direction and is maximum in the axis north / south.

Best Regards

[GOLDEN LILLY]

Yes, it is necessary to put a compass directly visible to the operator to know where is north and south, as this lrl, accordingly, will detect only in north and south directions. However, mine detects not north and south but NE and SE. Why?...

regards...

[GOLDEN LILLY]

Excuse me, it is NW (not NE) and SE where my lrl respond to compass effect...

Regards...

[FrancoItaly]

It is not important the direction of the compass effect, it is instead important that there is not the compass effect and this is achieved by reducing the sensitivity.

[sakher]

hello my friends
i am read all of posts in this project and i thank you so much and thank you mr.francoItaly
my name is sakher a new member in this forum
please help me ..i want find the last PCB of display stage with 8mhz can you help
sory for english .

[FrancoItaly]

this is the pcb by Dream man who really did a good job.

[pigeon]

hi all

I made the dream man version for the second time but it does not function.

help me pelase